JPH0325880Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a holder that is attached to the main shaft of a machine tool and holds a rotary cutting tool.

Conventional technology Traditionally, rotary cutting tools such as drills, reamers, end mills, and boring tools have been attached to machine tools such as drill presses, boring machines, or machining centers that automatically perform many types of processing with one device. Therefore, a rotary cutting tool holder is used which holds these rotary cutting tools at one end and is fixed to the main shaft of the machine tool at the other end.

This type of rotary cutting tool holder can be attached to the spindle using a tapered surface formed on the outer circumferential surface of the end opposite to the side that holds the tool, and a tapered surface formed on the inner circumferential surface of the spindle. This is done by being brought into close contact with the surface.

However, when attaching the holder to the spindle in this way, the two tapered surfaces do not necessarily come into close contact with each other due to wear associated with attachment and detachment, or due to adhesion of cutting chips, dust, etc. An installation error occurs in which the center line of the blade is tilted, and a decrease in machining accuracy is unavoidable.

In order to solve such problems, the present applicants have proposed a holder main body fixed to the main shaft of a machine tool and a rotary cutting machine at one end in the application of Japanese Patent Application No. 58-126768 and Japanese Patent Publication No. 61-7894. Disposed concentrically with the holder body provided with the tool attachment portion, and connected to the holder body at the end opposite to the side where the rotary cutting tool attachment portion is provided so as to be capable of slight relative displacement and to transmit rotational torque. A rotary cutting machine that includes a rotating shaft and a casing that is relatively rotatably attached to the outside of the rotating shaft and that engages with a positioning member provided in a fixed position around the main shaft to ensure positioning, thereby positioning the rotating shaft. A tool holder was proposed.

In this way, the rotating shaft is positioned by the casing that is accurately positioned by the fixed positioning member provided around the main shaft, so the holder body to which the rotating shaft is connected is simply moved by the main shaft. The tool can be positioned with high precision regardless of installation errors of the holder body relative to the main shaft due to wear or adhesion of cutting chips, dust, etc. to the contact surface between the main shaft and the holder main shaft.
High precision machining can be achieved.

Problems that the invention aims to solve However, when machining a workpiece, there are cases where it is necessary to orient the rotary cutting tool in a direction different from the direction from the rear end of the machine tool's main shaft to the front end. However, in the rotary cutting tool holder according to the above application, since the rotary cutting tool is oriented from the rear end side of the main shaft to the front end side, when the above necessity arises, the direction of the workpiece can be changed. It is troublesome to have to change the parts, and jigs and the like are required for this purpose, resulting in an increase in cost.

Means for Solving the Problems The present invention was devised to solve the above-mentioned problems, and for that purpose, a holder body that is removably fixed to the main shaft of a machine tool, and b the holder. a rotating shaft disposed concentrically with the main body and connected at one end to the holder main body so as to be relatively displaceable and capable of transmitting rotational torque; and (d) a positioning member that is attached to the outside of the rotating shaft so as to be relatively rotatable, and is pressed by the biasing force of the elastic member against a positioning member that is fixedly provided around the main shaft when the holder main body is fixed to the main shaft. a casing that engages with the positioning member to accurately position the centerline position and the angular position around the centerline; f are rotatably held while protruding from the casing in different directions, and have a rotary cutting tool attachment part at the tip; The transmission mechanism is configured to include a transmission mechanism.

Functions and Effects According to the rotary cutting tool holder configured as described above, the tool is attached to the tool holder that is held by the casing in a posture that is not located on the axis of the rotating shaft, and the tool holder rotates. By appropriately determining the attitude with respect to the shaft, machining can be performed in various directions, such as directions inclined to the axis of the rotating shaft, without changing the orientation of the workpiece.

In addition, since the tool holder is accurately positioned via the casing by a positioning member fixedly provided around the spindle, it is positioned with high accuracy regardless of the mounting accuracy of the holder body to the spindle. Accurate machining becomes possible. In addition, even though the tool holder is connected to the holder body via the rotating shaft and is far from the main shaft, it is held by the casing that engages with the positioning member, so the tool holding rigidity is increased. You can perform heavy cutting without running out of power.

Furthermore, the holder body and the rotating shaft are urged toward each other in the axial direction by the elastic member, and when the holder body is fixed to the main shaft of the machine tool, the casing is transmitted through the rotating shaft. The holder is pressed against the positioning member by the biasing force of the elastic member, engages with it, and is positioned. Therefore, in order to attach the rotary cutting tool holder to a machine tool, it is only necessary to fix the holder body to the main shaft, and the casing Since there is no need to fix the rotary cutting tool holder to the main body of the machine tool with bolts or the like, the rotary cutting tool holder can be easily and quickly attached and detached, and this also has the effect of improving machining efficiency.

Embodiment Hereinafter, a case in which the present invention is applied to a rotary cutting tool holder for a machining center will be described in detail based on the drawings.

In FIG. 1, 10 is a main shaft of a machining center that has a cylindrical shape and is driven to rotate around its axis.A rotary cutting tool holder (hereinafter referred to as a holder) 12 is attached to the tip of the main shaft 10. ing.

The holder 12 includes a holder body 14 that is removably fixed to the main shaft 10. Holder body 1
4 is a fixing member 1 having an outer peripheral tapered surface 16 formed thereon;
8, and a torque transmitting member 24 that is fitted into a through hole 20 provided on the axis of the fixing member 18 from the large diameter side of the fixing member 18 and fixed by a bolt 22 and a positioning pin (not shown). A pull stud 26 is fixed to the small diameter end of the fixing member 18 and protrudes in the axial direction thereof, and a radially outward flange portion 28 is provided on the outer periphery of the fixing member 18 on the large diameter side. ing.
A notch 30 is formed in the flange portion 28,
When the holder main body 14 is pulled into the main shaft 10 and the outer circumferential tapered surface 16 of the fixing member 18 comes into close contact with the inner circumferential tapered surface 32 formed in the cylindrical portion on the distal end side of the main shaft 10, the notch 30 is inserted into the main shaft 10. It engages with a key 34 fixed to the tip of the main shaft 10 and prevents relative rotation between the main shaft 10 and the fixed member 18.

On the other hand, a through hole 36 is also formed on the axis of the torque transmitting member 24, and a small diameter portion 40 of a rotating shaft 38 having a stepped cylindrical shape has a slight gap in the radial direction within the through hole 36. They are inserted concentrically.
A bolt 4 is attached to the end surface of the rotating shaft 38 on the small diameter portion 40 side.
2 is fixed in a state protruding from the through hole 36, and the head of the bolt 42 and the torque transmission member 24
The rotating shaft 38 is always urged toward the torque transmitting member 24 by a disc spring 44, which is an elastic member inserted between the rotary shaft 38 and the torque transmitting member 24. That is, the rotating shaft 38 and the torque transmitting member 24 are capable of relative movement in the direction of their axes against the biasing force of the disc spring 44, and a slight relative displacement of their axes is possible. In other words, the rotation shaft 38 is connected in such a way that slight radial deviation and inclination of the axis of the rotating shaft 38 with respect to the axis of the torque transmission member 24 is tolerated.
Further, a stepped pin 46 is fitted into the side wall of the torque transmitting member 24 by penetrating the side wall in the radial direction, and the end of the pin 46 protruding from the inner circumferential surface of the torque transmitting member rotates. By being fitted into the notch 48 formed in the small diameter portion 40 of the shaft 38, the rotational torque transmitted from the main shaft 10 to the fixed member 18 is transmitted to the rotation shaft 38 via the torque transmission member 24. There is.

A portion of the rotating shaft 38 protruding from the torque transmitting member 24 is rotatably held by a cylindrical casing 50. The casing 50 is arranged concentrically with the holder body 14 and has bearings 52,5.
A first casing 58 that holds the rotating shaft 38 via 4, 56, and whose center line is aligned with the first casing 58.
The second casing 60 is fixed to the end of the first casing 58 on the opposite side to the side facing the holder main body 14 while being inclined at a certain angle with respect to the center line of the second casing 60. A shaft-shaped tool holder 66 is rotatably held via two tapered roller bearings 62 and 64. Tool holder 66
The end opposite to the side facing the rotating shaft 38 is made to protrude from the second casing 60, and the reamer 7 as a rotary cutting tool is held by a collet chuck 68 as a tool holding part provided at this part.
0 is retained. The tool holder 66 and the rotating shaft 38 are connected by meshing bevel gears 72 and 74 attached to opposite ends, respectively, so that the rotation of the rotating shaft 38 is coupled to the tool holder 66. It is beginning to be transmitted. That is, in this embodiment, these bevel gears 72,
74 constitutes a rotation transmission mechanism, and the tool holder 66 is connected to the rotation shaft 38 of both bevel gears 72, 74 and the tool holder 66 with respect to the axis of the rotation shaft 38.
The workpiece is rotated at an angle that is the sum of the inclination angles with respect to the respective axes of the spindle 10, and the workpiece to be processed is machined by the reamer 70 in a direction that is inclined at the inclination angle with respect to the axis of the main spindle 10. It becomes. Note that the inclination angle of the teeth of the bevel gears 72 and 74 is appropriately determined by the inclination angle with respect to the axis of the main shaft 10 in the processing direction to be applied to the workpiece, and the inclination angle of the second casing 60 with respect to the first casing 58 is determined accordingly. It is determined.

An outer peripheral tapered surface 80 is formed on the outer peripheral surface of the end of the first casing 58 facing the main shaft 10, and the diameter becomes smaller toward the end of the first casing 58, that is, toward the holder main body 14, and An annular flange portion 8 protruding (radially outward) in a direction perpendicular to the center line of the first casing 58 on the large diameter side of the outer peripheral tapered surface 8
2 is provided. On the other hand, an annular positioning member 84 is fixedly provided on the main body of the machining center around the tip side of the main shaft 10, and the outer peripheral tapered surface of the first casing 58 is formed on the inner circumferential surface of the positioning member 84 on the tip side. An inner peripheral tapered surface 86 corresponding to 80 is formed. Therefore, when the pull stud 26 of the holder 12 is pulled into the main shaft 10, the outer circumferential tapered surface 80 of the first casing 58 and the inner circumferential tapered surface 86 of the positioning member 84 are brought into close contact, and the flange portion 82 is By bringing the end surface into contact with the distal end surface 88 of the positioning member 84, the first casing 58 is accurately positioned and fixed to the positioning member 84.

In addition, a notch 90 is formed in the flange portion 82, so that when attaching the holder 12 to the main shaft 10,
By engaging this notch 90 with a key 92 fixed to the tip of the positioning member 84, rotation of the first casing 58 can be reliably prevented.

Furthermore, the holder body 14 of the first casing 58
A plurality of recesses 94 are formed on the end surface facing the holder body 14, and a stepped pin 96 that engages with the recess 94 is fixed to the flange portion 28 provided on the fixing member 18 of the holder main body 14. These recesses 94, pins 96, and disc springs 44,
A relative rotation prevention mechanism is configured to prevent relative rotation between the holder main body 14 and the first casing 58. That is, when the holder 12 is removed from the main shaft 10, the recess 94 and the pin 96 are engaged by the urging force of the disc spring 44, thereby preventing relative rotation between the first casing 58 and the holder main body 14. This results in a locked state.

When attaching the holder 12 to the main shaft 10, the holder 12 is held in the annular groove 98 formed in the first casing 58 by an arm of a machining center (not shown) and inserted into the main shaft 10. At this time, the flange portion 28 of the fixing member 18
A notch 30 formed in the main shaft 10, a key 34 fixed to the main shaft 10, and a flange portion 8 of the first casing 58.
2 and the key 92 fixed to the positioning member 84 are formed in the same phase, and the main shaft 10 is always stopped at a constant rotational position, and the arm is always rotated in the same phase in the annular groove. By gripping 98, the notch 30 and the key 34 and the notch 90 and the key 92 are brought into engagement, respectively.

The holder main body 14 inserted into the main shaft 10 in this manner is drawn into the main shaft 10 by the pull stud 26 being pulled by the drawbar. At this time, since the holder main body 14 and the first casing 58 are urged toward each other by the disc spring 44, the pull stud 26
When the holder body 14 is pulled into the main shaft 10, the first casing 58 first comes into contact with the positioning member 84, and then the holder body 14 is slightly pulled away from the first casing 58 against the biasing force of the disc spring 44, so that the outer periphery The tapered surface 80 is fixed in close contact with the inner circumferential tapered surface 86. That is, the first casing 58 and the positioning member 84 are tightly fixed by the biasing force of the disc spring 44, and in this way, the holder main body 14 is separated from the first casing 158 and fixed. At the same time, the pin 96 is removed from the recess 94, and the engagement between the first casing 58 and the holder main body 14 is released, allowing the two to rotate relative to each other.

As is clear from the above description, in the holder 12 of this embodiment, the tool holder 66 that holds the reamer 70 is installed at an angle with respect to the axis of the rotating shaft 38, so that the workpiece and tool holder body 6
By relatively moving the tool holder 66 in a direction parallel to the axis of the tool holder 66, machining in a direction inclined to the axis of the main spindle 10 can be performed without tilting the workpiece.

Further, the tool holder 66 is accurately positioned by a positioning member 84 via the second casing 60 and the first casing 58 that hold it, and the holder body 14 is solidly attached to the main shaft 10.
Since the rotary shaft 38 and the rotary shaft 38 are connected to each other in such a manner that a slight relative displacement is possible, the positional accuracy of the reamer 70 is kept high regardless of the mounting error of the holder main body 14 with respect to the main shaft 10.

Furthermore, the reamer 70 is attached to a tool holder 66 connected to the rotating shaft 38, and
The main shaft 10 compared to the case where it is directly attached to the
Although the distance from the tool holder 66 is longer,
Since it is firmly supported by the positioning member 84, the first casing 58, and the second casing 60, the holding rigidity of the reamer 70 is not impaired, and processing can be performed with high precision.

As shown in FIG. 2, the rotation transmission mechanism that transmits the rotation of the rotating shaft 38 to the tool holder 66 is such that the angle of inclination of the teeth with respect to the axes of the rotating shaft 38 and the tool holder 66 is the same as that of the bevel gear 72, Bevel gears 100 and 102 smaller than 74 and having different meshing states
It may also be configured by In this case, bevel gear 1
Since 00 and 102 are lined up almost horizontally,
Accordingly, the shapes of the first casing 104 and the second casing 106 are different from those of the first and second casings 58 and 60.

Further, as shown in FIG. 3, yoke portions 110 and 112 are formed at the opposing ends of the rotating shaft 38 and the tool holder 66, respectively, and these yoke portions 110 and 112 are connected to the connecting members 114 and 2. A more rotatable connection of the book pins 116, 118 may also be provided. That is, the rotating shaft 38 and the tool holder 66 are connected by a so-called universal joint, and the first casing 5
8 is further divided into two casings for convenience of assembly.

Furthermore, as shown in Fig. 4, the constant velocity joint 1
20 constitutes a rotation transmission mechanism, the rotation shaft 3
8 and the tool holder 66 can be rotated at a constant angular speed. To briefly explain the configuration, the rotation axis 3
An outer race 122 is provided at the lower end of the tool holder 66, and an inner race 124 is provided at the upper end of the tool holder 66, and a plurality of balls 126 are held by a retainer 128 across the grooves of both. By doing so, the rotation of the rotary shaft 38 is transmitted to the tool holder 66 at a constant speed. Although the illustrated constant velocity joint 120 is of a fixed bar field type, it is also possible to adopt another type such as a tripod type.

Yet another embodiment of the invention is shown in FIG. In this embodiment, the tool holder 130 is disposed with its axis perpendicular to the axis of the rotating shaft 132, so that machining can be performed in a direction perpendicular to the axis of the main spindle 10. be. That is, the tool holder 130 and the rotating shaft 132 are connected by meshing bevel gears 134 and 136, as in the embodiment shown in FIG. The second casing 140 is rotatably held via bearings 142 and 144 by a second casing 140 disposed perpendicularly to the second casing 140 . Tool holder 13
The portion protruding from the second casing 140 of 0 has a large diameter, and a joint member 152 having an engaging protrusion 150 is fitted into a bottomed hole 148 formed at the center of this large diameter portion 146. Together with the large diameter portion 146, it constitutes a rotary cutting tool holder. The coupling member 152 is moved forward and backward in the axial direction by a screw member 153 and a cam mechanism (not shown), and is engaged at the engagement protrusion 150 with an engagement hole 158 formed at one end of an adapter 156 provided with a tip 154. together,
The adapter 156 is fixed to the tool holder 130.

The other configurations, operations, and effects are similar to those of the embodiment shown in FIG. 1, and corresponding parts are designated by the same reference numerals and detailed explanations will be omitted.

Yet another embodiment of the invention is shown in FIG. In this embodiment, the axis of the tool holder 160 is aligned with the axis of the rotating shaft 162 in order to perform back chamfering of a hole or machining a blind hole from the back of the work without changing the orientation of the work. The rotary cutting tool holders are arranged parallel to each other, and a rotary cutting tool holder is provided at the end of the tool holder 160 on the main shaft 10 side. That is, a bottomed hole 166 that opens toward the main shaft 10 is formed in the center of the tool holder 160, and a drill 168 as a rotary cutting tool is fitted therein with its rotation prevented by a set screw 169. This bottomed hole 1 of the tool holder 160
The portion where 66 is formed functions as a tool holding portion.

The first casing 172 is fixed to the tip of the first casing 170 that rotatably holds the rotating shaft 162 in such a manner that its center line is perpendicular to the center line of the first casing 170, and the second casing 172 A tool holder 160 is rotatably held via bearings 174 and 176 by the end opposite to the side fixed to the first casing 170 . Second casing 17 of rotating shaft 162
A small diameter gear 178 is housed in the
In addition, gears 180 having the same diameter as the gear 178 are attached to portions of the tool holder 160 corresponding to the gear 178, and these gears 178 and 180 are meshed with a large diameter gear 182 to rotate. The rotation of the shaft 162 is transmitted to the tool holder 160 at a constant speed. That is, in this embodiment, these three gears 17
8, 180, and 182 constitute a rotation transmission mechanism.

The rotary cutting tool holder of this embodiment is also attached to the main shaft 10 in the same manner as the embodiment shown in FIG.
Since the rotating shaft 162 is positioned more firmly and accurately, the rotating shaft 162 is lengthened in order to perform machining with the drill 168 facing the main shaft 10 side.
Main shaft 10 connected via 8, 180, 182
Even though the distance from the drill 168 to the drill 168 is considerably long, machining can be performed with high precision.

Furthermore, it is also possible to arrange the tool holder so that its axis three-dimensionally intersects with the axis of the rotating shaft.In this way, a plurality of tool holders can be provided and the tool can be used in two or more directions. Can be processed.

Although not illustrated in detail, the present invention can be implemented with various modifications and improvements based on the knowledge of those skilled in the art.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing a rotary cutting tool holder which is an embodiment of the present invention. FIGS. 2 to 4 are front sectional views showing other embodiments of the rotation transmission mechanism. FIG. 5 is a front sectional view showing another embodiment of the present invention, and FIG. 6 is a front sectional view showing still another embodiment. 10...Main shaft, 12...Rotary cutting tool holder (holder), 14...Holder body, 38...Rotating shaft, 44...Disc spring, 50...Casing, 66
. . . Tool holder, 68 .
...Positioning member, 86...Inner peripheral tapered surface, 10
0,102...Bevel gear (rotation transmission mechanism), 11
0,112... Yoke part (rotation transmission mechanism), 11
4... Connection member (rotation transmission mechanism), 116, 11
8...Pin (rotation transmission mechanism), 122...Outer race (rotation transmission mechanism), 124...Inner race (rotation transmission mechanism), 126...Ball (rotation transmission mechanism), 128...Retainer (rotation transmission mechanism) ,
130... Tool holder, 132... Rotating shaft, 13
4,136...Bevel gear (rotation transmission mechanism), 14
6...Large diameter part (rotary cutting tool holding part), 152...
...Joint member (rotary cutting tool holding part), 160...
Tool holder, 162... Rotating shaft, 178, 18
0,182...Gear (rotation transmission mechanism).

Claims (1)

[Claims for Utility Model Registration] A holder body that is removably fixed to the main shaft of a machine tool, and a holder body that is arranged concentrically with the holder body and connected to the holder body at one end so that it can be moved relative to the holder body and can transmit rotational torque. an elastic member that biases the holder main body and the rotating shaft toward each other in the axial direction; and an elastic member that is attached to the outside of the rotating shaft so as to be relatively rotatable, and the holder main body is fixed to the main shaft. When the positioning member is fixedly provided around the main shaft, it is pressed by the biasing force of the elastic member and engages with the member for positioning, thereby accurately positioning the centerline position and the angular position around the centerline. a casing that is rotatably held in the casing with a tip protruding from the casing in a direction different from the direction from the holder main body side toward the rotating shaft side, and a rotary cutting tool mounting portion is attached to the tip portion; A rotary cutting tool holder comprising: a tool holder; and a rotation transmission mechanism that is provided in the casing and transmits rotation of the rotation shaft to the tool holder.